Modular tire inflator

ABSTRACT

A tire inflation apparatus for inflating a tire mounted on a rim comprises an inflation head mounted to a moveable inflation shaft of a head position cylinder and an assist cylinder mounted to a frame member, with the frame member and assist cylinder positioned above the inflation location. The assist cylinder includes a moveable assist shaft operatively connected to the inflation shaft by a moveable cross member whereby the head position cylinder and assist cylinder cooperatively operate to selectively position the inflation head. The inflation head is positioned in a retracted position by vertical upward extension of the assist shaft and positioned in a tire engaging position by vertical downward retraction of the assist shaft. A fluid passage in the inflation shaft may deliver pressurized gas into a tire inflation cavity of the inflation head for inflating a tire when the inflation head is sealed against the tire.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority of U.S. provisional application,Ser. No. 61/012,599 filed Dec. 10, 2007, by Hoenke for MODULAR TIREINFLATOR which is hereby incorporated herein by reference in itsentirety.

BACKGROUND AND TECHNICAL FIELD OF THE INVENTION

The present invention is directed to an apparatus and method forinflating a tire assembled to a wheel.

Tire inflators are used in the mass assembly of tire and wheel rims toexpedite inflation of the tire relative to inflating through the tirevalve. Tire inflators traditionally include a portion that movesrelative to the tire and wheel assembly for contacting and maintaining asidewall of the tire in an orientation deflected from the wheel rimduring the inflation of the tire. The moveable portion of the tireinflator is typically moved in a vertical direction as guided by guiderods or the like extending downwardly and between the moveable portionand a stationary portion adjacent the tire and wheel rim assembly. Largevolumes of pressurized air are delivered to the assembly from one sideor the other of the tire and wheel assembly. That is, pressurized airmay be delivered through the side contacted by the moveable portion ofthe tire inflator or may be delivered from a bottom area opposite themoveable portion of the tire inflator. Tire inflation apparatuses mayinclude mechanisms to adjust the machines to inflate variously sizedtire and wheel combinations. Bellows or air cylinders may be used onsuch apparatuses to drive the mechanisms that adjust the machines.

Debris, such as tire debris, poor lubrication, or alignment errorscausing the moveable portion to tilt or become misaligned on the guiderods, however, are problematic to such systems in that the moveableportion may bind. Thus, the timing operation of the tire inflator may bedisrupted and/or damage to the guide rods, moveable portion, and/or tireand wheel assembly may result. Still further, debris can cause problemsto systems that inflate from beneath a tire and wheel assembly as aresult of the debris clogging valves and seals. The use of bellowsincreases the overall moving mass and height requirement of tireinflators and may require the travel distance of the movable portion toincrease. This increase in height and moving mass, thus, can increasethe cycle time and power requirements of inflation apparatuses.

SUMMARY OF THE INVENTION

A tire inflation apparatus in accordance with the present inventionpositions a head position cylinder and assist cylinders used forimparting and guiding motion of an inflation head above the inflationhead, and above the tire and wheel assembly to be inflated. Pressurizedgas is delivered to the inflation head via a fluid passageway formed inthe shaft of the head position cylinder. The inflation head may includeboth an inner and outer bell assembly, with the outer bell assemblybeing selectively attachable and detachable from the inner bellassembly. When detached from the inner bell assembly, the outer bellassembly may be retained or stored such that the inner bell assembly isable to move independently. Positioning of the inflation head may becontrolled with a position sensor and a proportional position control,such as a proportional directional control valve, integrated with acontrol system for monitoring the location of the inflation head andcontrolling the flow of hydraulic fluid and/or compressed air to thehead position cylinder and/or assist cylinders to direct movement of andposition the inflation head.

According to an aspect of the present invention a tire inflationapparatus for inflating a tire mounted on a rim comprises a frame memberpositioned above a tire and rim assembly inflation location at which atire mounted on a rim is received to inflate the tire and an inflationhead movable between a retracted position and a tire engaging position,with the inflation head defining a tire inflation cavity and beingadapted to form a seal with a tire when positioned against a tire in thetire engaging position where pressurized gas is deliverable into theinflation cavity to inflate a tire when the inflation head is sealedagainst a tire in the tire engaging position. The inflation apparatusfurther includes a head position cylinder including a fixed headposition cylinder base and a moveable inflation shaft. The inflationhead is mounted to the inflation shaft whereby movement of the inflationshaft selectively positions the inflation head between the retractedposition and the tire engaging position. The inflation apparatus alsoincludes a first assist cylinder mounted to the frame member above theinflation location, with the first assist cylinder including a fixedfirst assist cylinder base and a moveable first assist shaft. The firstassist shaft is operatively connected to the inflation shaft by amoveable cross member with the head position cylinder and first assistcylinder cooperatively operating to selectively position the inflationhead and the inflation head being positioned in the retracted positionby vertical upward extension of the first assist shaft from the firstassist cylinder base and positioned in the tire engaging position byvertical downward retraction of the first assist shaft into the firstassist cylinder base.

A fluid passage may extend at least partially through the inflationshaft, with the fluid passage forming an outlet in the inflation cavityfor the delivery of pressurized gas through the fluid passage into theinflation cavity. In an embodiment, the cross member is positioned andmoveable vertically above the frame member, and the first assistcylinder base member and head position cylinder base are mounted to theframe member. Also in an embodiment, the inflation shaft includes alower portion extending and retracting vertically downward from the headposition cylinder base and an upper portion extending and retractingvertically upward from the head position cylinder base with the upperportion of the inflation shaft connected to the moveable cross member.The first assist cylinder may be a hydraulic or pneumatic cylinder.

According to another aspect of the present invention, a tire inflationapparatus for inflating a tire mounted on a rim comprises a frame memberpositioned above a tire and rim assembly inflation location at which atire mounted on a rim is received to inflate the tire, at least oneretainer mounted to the frame member, and an inflation head movablebetween a retracted position and a tire engaging position with theinflation head defining a tire inflation cavity and adapted to form aseal with a tire when positioned against a tire in the tire engagingposition. The apparatus further includes a head position cylinderincluding a fixed head position cylinder base and a moveable inflationshaft, the inflation head being mounted to the inflation shaft wherebymovement of the inflation shaft selectively positions the inflation headbetween the retracted position and the tire engaging position. Theinflation shaft includes a fluid passage extending at least partiallythrough the inflation shaft with the fluid passage forming an outlet inthe inflation cavity such that pressurized gas is deliverable throughthe fluid passage to the inflation cavity to inflate a tire when theinflation head is sealed against a tire in the tire engaging position.The inflation head comprising an outer bell assembly and an inner bellassembly with the outer bell assembly being selectively attachable tothe inner bell assembly with the outer bell assembly forming a seal witha tire when engaged with the inner bell assembly and the outer bellassembly being positioned against a tire in the tire engaging position.The outer bell assembly being selectively detachable from the inner bellassembly with the at least one retainer adapted to hold the outer bellassembly in the retracted position when the outer bell assembly isdetached from the inner bell assembly. The inner bell assembly beingselectively moved independently of the outer bell assembly when theouter bell assembly is detached from the inner bell assembly with theinner bell assembly forming a seal with a tire when disengaged from theouter bell assembly and the inner bell assembly is positioned against atire.

In an embodiment the inner bell assembly includes a plurality of lockingpins with the outer bell assembly including a moveable outer belllocking plate having a plurality of locking apertures for selectivelyreceiving the locking pins. The outer bell locking plate being moveableto selectively engage the outer bell assembly with the inner bellassembly and enable the outer bell assembly to be disengaged from theinner bell assembly. The outer bell assembly may include a locking plateactuator adapted to rotate the outer bell locking plate relative to theinner bell assembly for engaging and disengaging the locking pins withthe locking apertures. The outer bell assembly includes at least one taband with the at least one retainer comprising a clamp adapted to engagethe tab to hold the outer bell assembly in the retracted position whendetached from the inner bell assembly. The clamp may be actuated by aretention cylinder.

According to another aspect of the present invention, a tire inflationapparatus for inflating a tire mounted on a rim comprises a frame memberpositioned above a tire and rim assembly inflation location at which atire mounted on a rim is received to inflate the tire and an inflationhead movable between a retracted position and a tire engaging position,with the inflation head defining a tire inflation cavity and adapted toform a seal with a tire when positioned against a tire. The inflationapparatus further includes a controller, a position gauge, a positioncontrol valve, and a head position cylinder. The head position cylinderincludes a fixed head position cylinder base and a moveable inflationshaft with the inflation head mounted to the inflation shaft wherebymovement of the inflation shaft selectively positions the inflation headbetween the retracted position and the tire engaging position. Theposition gauge operatively detects the position of the inflation headand the controller is operatively connected with the position gauge suchthat the controller receives position information of the inflation head.The position control valve is operatively connected with the controllerand adapted to control movement of the inflation head, with thecontroller adapted to operate the position control valve to directmovement of the inflation head in response to position information ofthe inflation head received from the position gauge.

In an embodiment the tire inflation apparatus further includes apressure transmitter operative to monitor pressure at the tire inflationcavity and transmit input signals indicative of the pressure to thecontroller, wherein the controller is adapted to operate the inflationapparatus in response to the input signals. Also in an embodiment thehead position cylinder comprises a hydraulic cylinder and the inflationshaft includes a piston inside the head position cylinder base, whereinthe position control valve comprises a hydraulic proportional flowcontrol valve adapted to supply and remove hydraulic fluid from bothsides of the piston. The controller may also receive data input signalscomprising information indicative of a tire and wheel assembly to beinflated, with the controller operable to control operation of theinflation apparatus in response thereto.

Therefore, an inflation apparatus is provided that may convenientlydeliver pressurized tire inflation fluid, such as compressed air,through a shaft of the head position cylinder, thereby simplifying thedelivery of pressurized gas to a tire for inflation. Upwardly extendingassist cylinders may be used to aid positioning an inflation head of theapparatus between a retracted and extended position such shafts of theassist cylinders are operated out of the tire and wheel assemblyinflation location to avoid contamination. The inflation apparatus mayalso be provided with a guide system mounted above the inflation headand adjacent an assist cylinder and/or head position cylinder to guidemovement of the inflation head above and away from the debris generatingzone of the inflation apparatus. A position sensor, pressuretransmitter, and a proportional position control valve integrated with aclosed loop control system can be incorporated to monitor and controlthe position of the inflation head of the inflation apparatus. Theinflation apparatus further enables differently sized wheel and tirecombinations to be conveniently inflated without time consumingequipment changes.

These and other objects, advantages, purposes and features of thisinvention will become apparent upon review of the followingspecification in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a tire inflation apparatus in accordancewith the present invention;

FIG. 2 is a side elevation view of the tire inflation apparatus of FIG.1;

FIG. 3 is a side elevation view of an upper portion of the tireinflation apparatus of FIG. 1 showing the inflation head in a retractedposition;

FIG. 3A is a top plan view of the tire inflation apparatus portion ofFIG. 3;

FIG. 4 is a front elevation view of the tire inflation apparatus portionof FIG. 3;

FIG. 5 is sectional view along the line A-A of FIG. 4;

FIG. 6 is a side sectional view of an upper portion of the tireinflation apparatus of FIG. 1 showing the inflation head in a tireengaging position;

FIG. 6A is a side sectional view of the tire inflation apparatus portionof FIG. 6 showing the inner bell assembly in a tire engaging positionand the outer bell assembly detached;

FIG. 7 is an enlarged sectional view of the inflation head of FIG. 5;

FIG. 8 is an upward perspective view of the inflation head of the tireinflation apparatus of FIG. 1 shown extended from a retracted position;

FIG. 9 is an upward perspective view of an outer bell assembly portionof the inflation head of the tire inflation apparatus of FIG. 1 shown ina retracted position and an inner bell assembly portion of the inflationhead shown extended from a retracted position;

FIG. 10 is a downward perspective view of the inflation head of FIG. 8illustrating the inner bell assembly and outer bell assembly securedtogether;

FIG. 11 is a downward partial perspective view of the inflation head ofthe tire inflation apparatus of FIG. 1 illustrating the inner bellassembly and outer bell assembly unlocked for disengagement;

FIG. 12 is a side perspective view of the inflation head of the tireinflation apparatus of FIG. 1 showing the outer bell assembly in aretracted position such that the inner bell assembly is able to moveindependently of the outer bell assembly;

FIG. 13 is a close up perspective view of a portion of the outer bellassembly of FIG. 12 in a retracted position;

FIG. 14 is side perspective view of the tire inflation apparatus of FIG.1 illustrating a movable support arm positioned beneath a removable ringseal of the outer bell assembly;

FIG. 15 is a perspective view of the tire and wheel rim locatingapparatuses of the tire inflation apparatus of FIG. 1;

FIG. 16 is a schematic illustration of a hydraulic control system inaccordance with the present invention for use with the tire inflationapparatus of FIG. 1; and

FIG. 17 is a schematic illustration of an alternative hydraulic controlsystem in accordance with the present invention for use with a tireinflation apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described with reference to theaccompanying figures, wherein the numbered elements in the followingwritten description correspond to like-numbered elements in the figures.A tire inflation apparatus 30 is shown in FIGS. 1 and 2 to include abase 32 having a wheel and tire assembly input location 34, a wheelcentering apparatus 36, a tire centering apparatus 38, and an inflationhead 40 mounted to an inflation head positioning cylinder or inflationhead cylinder or head position cylinder or inflation cylinder 42. In theillustrated embodiment, inflation apparatus 30 also includes a pair ofassist cylinders 44, 46 located on either side of the inflation cylinder42. Inflation head 40 is used to inflate tires mounted to wheels orwheel rims, such as tire and wheel rim assembly 45 of FIG. 6 and tireand wheel rim assembly 47 of FIG. 6A. Inflation head 40 is caused tomove between, and is retained in, a retracted or stored position 48(FIG. 5) and a tire engaging position 50 (FIG. 6) by way of inflationcylinder 42 and assist cylinders 44, 46.

The positioning of inflation cylinder 42 and assist cylinders 44, 46 inan orientation above the assembly input location 34 aids in the properoperation of inflation apparatus 30 by avoiding or inhibiting assemblycontamination or debris from damaging or causing binding of inflationcylinder 42 and assist cylinders 44, 46 by being mounted away from thedebris generating zone associated with the tire and wheel assembly inputlocation 34. Moreover, as described below, inflation cylinder 42includes a fluid passage 52 (FIG. 5) enabling compressed gas to bedelivered at least partially through the inflation cylinder 42 and intoan inflation cavity 54 (FIG. 5) of the inflation head 40 for inflatingthe tire of a wheel and tire assembly 45 and 47.

As additionally described still further below, inflation head 40includes both an outer bell assembly 56 and an inner bell assembly 58 toenable inflation of differently sized wheel and tire assemblies 45, 47using inflation apparatus 30. Outer bell assembly 56 may be disconnectedand retained such that inner bell assembly 58 is able to move betweenthe retracted position 48 and tire engaging position 50 independently ofouter bell assembly 56. Outer bell assembly 56 also includes a removablering seal member 60 (FIGS. 3-7) that may be replaced with ring sealmembers of differing sizes to further enable inflation of differentlysized wheel and tire assemblies using inflation apparatus 30.

Referring now to FIGS. 3-7, inflation cylinder 42 and assist cylinders44, 46 are mounted to a fixed frame member 62, which in the illustratedembodiment is attached to and forms part of base 32. Inflation cylinder42 includes a moveable cylinder member, which in the embodiment shown isan inflation shaft 64 that is movably operated within a fixed cylindermember 66 mounted to the fixed frame member 62. Assist cylinders 44, 46each include moveable cylinder members, which in the embodiment shownare assist shafts 68, 70 affixed to a moveable cross member 71. Theassist shafts 68, 70 operate within fixed cylinder members 72, 74mounted to the fixed frame member 62. FIGS. 5 and 6 illustrate that oneend 75 of inflation shaft 64 is secured to the moveable cross member 71and that the inflation head 40 is mounted to the opposite end 76 ofinflation shaft 64. Movement of inflation shaft 64 and assist shafts 68,70 enables inflation head 40 to be positioned between the retractedposition 48 (FIG. 5) and an extended or tire engaging position 50 (FIG.6).

FIGS. 3A and 4 disclose the inclusion of an anti-rotation tower or braceor guide system 77 that includes a bracket 78 on fixed frame member 62,with bracket 78 including a guide rail 80 within which a guide member 82of cross member 71 is adapted to travel for guiding movement of crossmember 71 and inhibiting rotation of cross member 71 about thelongitudinal axis of inflation shaft 64. A single guide system 77 isdisclosed in the illustrated embodiment, however, additional guidesystems may be employed or an inflation apparatus may be constructedwithout the inclusion of such a brace. Still further, an alternativeguide system may be constructed, for example, as a cylinder having anextendable and retractable shaft.

As shown in FIGS. 3 and 5, a position transducer 84 is mounted tobracket 78 adjacent assist cylinder 44 for monitoring the stroke ofinflation shaft 64 and, correspondingly, the position of inflation head40. Position transducer 84 employs a magnet 86 affixed to moveable crossmember 71 such that position transducer 84 is able to supply positioninformation to a control system 88 (FIG. 16) as magnet 86 travels alongor adjacent position transducer 84. As described in more detail below,control system 88 is thereby able to accurately monitor and direct theextension and retraction of inflation head 40.

Cross member 71 moves above fixed frame member 62 with assist shafts 68,70 being extended vertically upwards to place inflation head 40 in theretracted position 48 and retracted into fixed cylinder members 72, 74to place inflation head 40 in the tire engaging position 50.

That is, upward extension of cylinders 44, 46 positions inflation head40 in the retracted position 48 and retraction of assist cylinders 44,46 positions inflation head 40 in the tire engaging position 50. Theconnection of double acting inflation shaft 64 and assist shafts 68, 70to cross member 71 above fixed frame member 62, along with the relativediameter of inflation shaft 64, provides for extension and retraction ofassist shafts 68, 70 to occur without the requirement of guide rods, orthe like, being placed or positioned adjacent wheel and tire assemblyinput location 34, as well as inhibits contamination of shafts 68, 70 bypositioning them above the wheel and tire assembly input location 34.

Assist cylinders 44, 46 are hydraulic cylinders, such as may be suppliedby the Parker Hannifin Corporation. Inflation cylinder 42 is a doublerod hydraulic cylinder in which hydraulic fluid may operate on eitherside of piston 90 (FIGS. 5 and 6). In the illustrated embodiment, assistcylinders 44, 46 are approximately 2.0 inch diameter cylinders andinflation cylinder 42 is approximately a 10.0 inch diameter cylinder.The size of inflation cylinder 42 provides an inflation shaft 64 able toresist side loads during the inflation process without apparatus 30requiring lower guide rods or systems depending downward from framemember 62. The connection of assist shafts 68, 70 to moveable crossmember 71 enables assist cylinders 44, 46 to be used to move inflationshaft 64 and, thus, inflation head 40. In this manner, lower volumes ofpressurized hydraulic fluid may be used to move or reposition inflationhead 40 as would be required if inflation cylinder 42 were used to moveinflation head 40 up and down due to the relative differences incylinder sizes. The larger diameter of inflation cylinder 42 may then beused to retain inflation head 40 in a particular position. For example,when placed against a tire in the tire engaging position 50, largeupward forces will be exerted on inflation shaft 64 during tireinflation. The larger diameter of inflation cylinder 42 is able toresist the upward force with acceptable hydraulic pressure. It should beappreciated that the relatively lower inflation air pressure in a tirewill create a large upward force due to the large cross sectional areaof inflation head 40. Thus, the subsequent hydraulic fluid pressurerequired to retain inflation head 40 in a particular position will behigher due to the smaller cross sectional area of inflation cylinder 42.The pressure in inflation head 42 could, for example, be between 10 to40 times higher than the tire inflation pressure. The operation andcoordination of inflation cylinder 42 and assist cylinders 44, 46 isdescribed in more detail below.

Alternatively, however, more, fewer, differently sized, alternativelyconfigured, or no assist cylinders may be used with a tire inflationapparatus. For example, as illustrated schematically in FIG. 17 anddiscussed below, alternative assist cylinders may be constructed aspneumatic cylinders. Pneumatic cylinders generally cost less thanhydraulic cylinders and also reduce the amount of hydraulic fluidrequired for a tire inflation apparatus, including reducing the powerrequired to pump the hydraulic fluid by a hydraulic fluid power supply.Further, an alternative tire inflation apparatus may be constructedwithout assist cylinders wherein the inflation cylinder is used to bothmove and retain an inflation head. Still further, inflation shaftshaving larger or smaller diameters may be used based on the tire size tobe inflated in accordance with the upward inflation forces being thereapplied.

Referring now to FIG. 7, inflation head 40 is shown to include thepreviously mentioned inner bell assembly 58 and outer bell assembly 56,and include a tire inflation cavity 54. The inner bell assembly 58 ismounted to the inflation shaft 64, with the inflation shaft 64 includinga fluid passage 52 that forms an outlet 94 in the inflation cavity 54.Pressurized gas, such as compressed air, nitrogen, or the like, may besupplied via a line or hose (not shown) affixed to a flange 96 onmoveable cross member 71 leading to the fluid passage 52 (FIGS. 5 and6). Thus, pressurized gas delivered through fluid passage 52 into cavity54 is used to inflate a tire mounted to a wheel.

As shown in FIGS. 5-7, an elongate hollow tube 93 may be positionedwithin fluid passage 52 of inflation shaft 64 and affixed to shaft 64 tosimultaneously move therewith. Tube 93 includes an angled lower end 95extending out of and away from outlet 94 of shaft 64, and includes, asshown in FIGS. 6 and 7, an upper end 97 connected to a pressuretransmitter or pressure transmitting device 99, with tube 93 andtransmitting device 99 thus forming a pressure sensing and transmittingassembly. Although not shown, upper end 97 may pass through a spacerblock (not shown) by way of pipe fitting elbows (not shown), with aflange 96 for receiving an air supply hose mounted to the spacer blocksuch that the spacer block is sandwiched between a flange, such asflange 96 of FIGS. 1-3, and cross member 71. Tube 93 enables theinflation or air pressure at cavity 54 to be measured by pressuretransmitting device 99 while minimizing the influence of high velocityair filling rate through passage 52. Inflation pressure informationmonitored by pressure transmitting device 99 may be used to control thesetting or operation of inflation apparatus 30. For example, inflationpressure information may be transmitted from pressure transmittingdevice 99 to a control system, such as control system 88 or 188described below in connection with FIGS. 16 and 17, with suchinformation being used to control the operation of apparatus 30.

In the illustrated embodiment fluid passage 52 extends the axial lengthof inflation shaft 64 with pressurized gas being delivered into one end75 and exiting the opposite end 76 into cavity 54. However, analternative inflation shaft may have a fluid passage extending only aportion of the length of such an inflation shaft. For example, a fluidpassage may be configured as a blind hole or a hole plugged at one end,with pressurized gas being supplied by a hose, tube, or the like,secured to an outer surface of the inflation shaft, such as by afitting. Still further, an alternative inflation shaft may include morethan one fluid passage with the additional fluid passage or passages,for example, be useful for providing control air to other devices insidethe inner bell assembly, providing inflation air, or otherwise. Aninflation shaft may also be provided with additional passages to allow,for example, wiring to be brought into inner bell assembly for use withother devices, such as pressure monitors, distance or object sensors, orthe like.

As previously noted, inflation head 40 comprises an outer bell assembly56 and an inner bell assembly 58. FIGS. 1-8 disclose outer bell assembly56 affixed to inner bell assembly 58. In this arrangement outer bellassembly 56 is moved up and down with inner bell assembly 58. Asunderstood from FIG. 7, inner bell assembly 58 is nested within outerbell assembly 56 such that outer bell assembly 56 will contact a tirewhen positioned in the tire engaging position 50. Outer bell assembly 56may thus be used during the inflation of larger tires and/or wheels,such as tire and wheel assembly 45 of FIG. 6, as compared to inner bellassembly 58, which is shown in FIG. 6A adjacent smaller tire and wheelassembly 47.

Outer bell assembly 56 includes an outer bell top plate 98, an outerbell housing 100 affixed to top plate 98, and ring seal member 60 thatis removably attached to housing 100 via clamps 104. An outer belllocking member or locking plate 106 is movably attached to top plate 98and is retained and sandwiched between top plate 98 and retention memberor retention ring 107, with retention ring 107 being secured to topplate 98. Locking plate 106 is used in the engaging and disengaging ofouter bell assembly 56 to inner bell assembly 58.

Ring seal member 60 includes a lower circumferential sealing edge 108that engages and seals against a tire sidewall when inflating a tireassembled to a wheel when the inflation head 40 is positioned in thetire engaging position. Ring seal member 60 further includes a sealinggroove 110 within which a seal, such as an o-ring (not shown) may beinstalled to provide a seal between ring seal member 60 and anattachment face 112 of housing 100. Ring seal member 60 includes anexterior flange 114 that mates with the attachment face 112 wherebyclamps 104 are used to secure ring seal member 60 to housing 100. Theability to remove ring seal member 60 enables alternatively sized ringseal members 60A (FIG. 14) to be secured to housing 100. Suchalternative ring seal members having circumferential sealing edgesdefining larger or smaller diameters enable inflation apparatus toinflate still further alternatively sized tires and/or wheel rimassemblies. When not in use, a ring seal member 102 may be stored on aring member support aim 116 that is pivotally attached to base 32. FIGS.1, 2, and 14 illustrate a ring member support arm 116 positionedadjacent to outer bell assembly 56 for installing or removing a ringseal member 60. When inflation apparatus 30 is used for inflating tiresmounted to wheels, support arm 116 is pivoted out from alignment withinflation head 40.

Outer bell housing 100 includes an internal circumferential chamfer 118that leads to a circumferential sealing surface 120 against which innerbell assembly 58 is sealed, as described below, to inhibit pressurizedgas supplied to cavity 54 from escaping between inner bell assembly 58and outer bell assembly 56.

Inner bell assembly 58 includes an inner bell housing 122 secured to aninner bell locking plate 124. Multiple locking pins 126 (FIGS. 7 and 12)extend from locking plate 124 and are used in the engagement of innerbell assembly 58 with outer bell assembly 56, as described below. Innerbell housing 122 includes a lower circumferential sealing edge 128 thatengages and seals against a tire sidewall when the outer bell assembly56 is disengaged from the inner bell assembly 58 and the inner bellassembly 58 is positioned in the tire engaging position and used toinflate a tire assembled to a wheel (see FIG. 6A).

An exterior circumferential sealing groove 130 is disposed on housing122 within which a seal, such as o-ring seal 132, is disposed forsealing against sealing surface 120 of outer bell housing 100. FIG. 7illustrates inner bell assembly 58 fully nested within outer bellassembly 56 in the arrangement whereby inner and outer bell assemblies58, 56 are secured and moved together. When outer bell assembly 56 isdisengaged from inner bell assembly 58 and inner bell assembly 58 ismoved between the retracted position 48 and the tire engaging position50 independently of outer bell assembly 56, however, inner bell assembly58 may not be caused to fully nest within outer bell assembly 56. Forexample, inner bell assembly 58 may only be retracted a distance suchthat lower sealing edge 128 of inner bell assembly 58 is flush or planaroriented with lower sealing edge 108 of outer bell assembly 56. As such,seal 132 of inner bell assembly 58 is not continuously moved againstchamfer 118 and scaling surface 120 of outer bell housing 100, therebyavoiding excessive wear of seal 132.

Referring now to FIGS. 10 and 11, the locking engagement of outer bellassembly 56 to inner bell assembly 58 will now be described. Movableouter bell locking plate 106 includes multiple apertures 134 forreceiving the locking pins 126 of inner bell assembly 58. Apertures 134are formed as elongated holes of overlapping and differing diameters ina keyhole style configuration. Locking pins 126 are constructed withenlarged beads 136 (FIG. 12) that are able to pass through the enlargedportion of apertures 134 (FIG. 11). After heads 136 are passed throughthe enlarged portion of apertures 134 an actuator, such as cylinder 138,is used to rotate locking plate 106. A base 140 of cylinder 138 ispivotally affixed to outer bell top plate 98 via bracket 141 and theshaft 142 of cylinder 138 is pivotally connected to an arm 144 connectedto movable locking plate 106. FIG. 11 illustrates shaft 142 extendedwhereby heads 136 are able to pass through apertures 134. Subsequently,shaft 142 may be retracted (FIG. 10) such that locking plate 106 isrotated and the smaller portion of apertures 134 are positioned beneathheads 136 whereby outer bell assembly 56 is secured to inner bellassembly 58. Cylinder 138 may be a pneumatic or hydraulic cylinder, ormay alternatively be configured as an electric actuator.

Referring now to FIGS. 8, 9 and 11-13, the retention of outer bellassembly 56 to enable inner bell assembly 58 to be operatedindependently of outer bell assembly 56 will now be described. Asunderstood from FIGS. 9 and 12, outer bell assembly 56 may be retainedin the retracted position 48 such that inner bell assembly 58 is able tobe extended and retracted independently of outer bell assembly 56.

Outer bell top plate 98 includes a pair of retention tabs 146A, 146B(FIGS. 7 and 13) disposed generally 180 degrees apart from each otherand a pair of retainers mounted to fixed frame member 62 are used toselectively engage tabs 146A, 146B. In the illustrated embodiment,retainers are constructed as clamps 150A, 150B having pivotal L-shapedarms 152A, 152B that are each selectively actuated by a pair ofactuators configured as cylinders 154A, 154B. When outer bell assembly56 is in the retracted position 48, extension of shafts 156A, 156B ofcylinders 154A, 154B causes arms 152A, 152B of clamps 150A, 150B to bepositioned underneath tabs 146A, 146B (FIGS. 9, 12, and 13).Conventionally, although not shown, retraction of shafts 156 disposesarms 152 in a generally downward pointing direction such that outer bellassembly 56 may be moved in unison with inner bell assembly 58.

FIGS. 7 and 13 further disclose the inclusion of centering buttons orcentering pins 158 on outer bell top plate 98. Centering pins 158 areadapted to contact a portion of fixed frame member 62 for accuratelylocating outer bell assembly 56 against fixed frame member 62 when outerbell assembly 56 is retained in the retracted position 48. In theillustrated embodiment, centering pin 158 is adapted to contact abushing 160 mounted within a centering pad 162 affixed to fixed framemember 62. Although not shown, three centering pins 158 are provided tolocate outer bell assembly 56 against fixed frame member 62. Alternativemeans of locating outer bell assembly 56 against fixed frame member 62may be employed and still function as intended within the scope of thepresent invention. For example, centering pins may directly contact thefixed frame member or alternative retainers used to secure an outer bellassembly may sufficiently locate the outer bell assembly without needfor centering pins.

When it is desired to operate inner bell assembly 58 independently ofouter bell assembly 56, outer bell assembly 56 is brought into theretracted position 48 such that centering pins 158 engage bushings 160.Clamps 150 are then actuated by cylinders 154 to cause arms 152 to bedisposed beneath tabs 146, as shown in FIGS. 9, 12, and 13.Subsequently, movable outer bell locking plate 106 is caused to rotatevia cylinder 138 whereby heads 136 of locking pins 126 are disposed atthe larger portion of apertures 134 such that inner bell assembly 58 maybe disengaged from outer bell assembly 56. Inner bell assembly 58 maythen be extended out of outer bell assembly 56. As noted, when innerbell assembly 58 is operated independently of outer bell assembly 56,inner bell assembly 58 does not need to be brought into fully nestedengagement with outer bell assembly 56 to inhibit wear of seal 132.

Alternatively configured and/or operated retainer mechanisms may be usedto retain outer bell assembly 56 in the retracted position 48 and stillfunction as intended within the scope of the present invention. Forexample, an outer bell top plate 98 may include more than two retainertabs, such as disposed 120 degrees about the top plate. Clamps may alsobe configured with other than L-shaped arms or retainers may beconfigured other than as clamps. For example, retention pins may beselectively inserted into apertures to hold an outer bell assembly inposition.

Although the above described inflation head 40 includes both an innerbell assembly 58 and an outer bell assembly 56, it should be appreciatedthat a tire inflation apparatus in accordance with aspects of thepresent invention may include only a single bell assembly, such as, forexample, a bell assembly that is generally or substantially similar toinner bell assembly 58.

As illustrated in FIGS. 1 and 15, a wheel rim centering apparatus 36 anda tire centering apparatus 38 may also be included on inflationapparatus 30. Wheel rim centering apparatus 36 and tire centeringapparatus 38 are used to center and hold the rim and tire, respectively,in axial alignment with one another and inflation head 40 prior toengagement of the tire by inflation head 40 for inflating the tire.Although not shown, tire and wheel rim assemblies may be brought to orremoved from inflation apparatus 30 by a conveyor system, robotichandling device, or the like.

Wheel rim centering apparatus 36 includes a support plate 164 havingthree conventional centering arms 166. Each centering arm 166 isconnected to an individual centering arm gear (not shown), with eachcentering arm gear in turn being meshed to a drive gear (also notshown). The drive gear is driven by pulley 168 and when so driven causescentering arms 166 to pivotally move in unison. When a wheel rim isplaced on support plate 164, centering arms 166 are outwardly rotated orpivoted in unison to engage an inside diameter, edge, or flange of therim. When so grasped, the rotational axis of the wheel rim is generallyaligned or centered relative to inflation head 40. Tire centeringapparatus 38 includes a pair of arms 170A, 170B having tire engagingrollers 172 affixed thereto at spaced positions. Arms 170 are moved inand out in unison by a pulley system 174 and are operated such thatinward movement of the arms 170 will align a tire mounted to a rim withinflation head 40.

Control system 88 of inflation apparatus 30 will now be discussed withreference to FIG. 16. Those portions of inflation apparatus 30illustrated schematically in FIG. 16 are identified using like numbersas used in FIGS. 1-15, with the reference suffix “S” added to the likeillustrated parts in FIG. 16. The schematically illustrated componentsinclude inflation head 40S, inflation cylinder 42S, inflation shaft 64S,piston 90S assist cylinders 44S, 46S, and moveable cross member 71S.

Control system 88 includes a pair of inflation cylinder valves 176, 178for controlling operation of inflation cylinder 42S, an assist cylindervalve 180, 182 for each assist cylinder 44S, 46S, respectively, aproportional position control 184, and a controller or processor, suchas a PLC or computer 186, or the like. Computer 186 may be preprogrammed with information regarding target data for the desiredpositioning of inflation head 40S to inflate various combinations oftire and wheel assemblies that may be inflated using inflation apparatus30, along with target tire inflation pressure information.

Valves 176, 178 operate as bypass and lock-up valves for controlling theflow of hydraulic fluid on either side of piston 90S. When inflationhead 40S is positioned against a tire in the tire engaging position 50,the valves 176, 178 controlling the flow of hydraulic fluid out ofinflation cylinder 42S above and below piston 90S are closed to preventor inhibit hydraulic fluid from being forced out of inflation cylinder42S due to the upward forces imparted to inflation shaft 64S during theinflation of the tire. Assist cylinder valves 180, 182 operate tocontrol the flow of hydraulic fluid into and out of assist cylinders44S, 46S. The extension and retraction of assist cylinders 44S, 46S byhydraulic fluid flowing through assist cylinder valves 180, 182 may becontrolled by computer 186 based on input signals discussed below.

Proportional position control 184 is electronically interfaced withcomputer 186, with computer 186 also receiving input signals 181 fromposition transducer 84 and input signals 183 from pressure transmittingdevice 99. Proportional position control 184 is adapted to control theflow of hydraulic fluid into and out of inflation cylinder 42S on eitherside of piston 90S in response to commands from computer 186 based oninput signals 181, 183. Computer 186, thus, is adapted to control theflow of hydraulic fluid into and out of inflation cylinder 42S toprovide finer control of the position of inflation head 40S. Computer186 is able to cause hydraulic fluid supplied from hydraulic powersupply 187 to flow through proportional position control 184 when valves176, 178 are closed. Moreover, computer 186 may additionally oroptionally receive input signals 185 from a reading or detecting device(not shown), such as a photo eye, a bar code scanner, vision system, orthe like, signaling the presence of a tire and wheel rim at installationapparatus 30 to initiate the process of inflating the assembled tire andwheel rim. Still further, such input signals 185 provided to thecomputer 186 may additionally provide specifications about the sizeand/or type of wheel rim and/or tire, whereby computer 186 may furthercontrol operation of installation apparatus 30 by controlling the use ofeither inner bell assembly 58 or outer bell assembly 56 to inflate thetire, or even signaling that an alternative ring seal member 60A may berequired to inflate a particular tire and wheel rim assembly based onpreprogrammed requirements. The preprogrammed specifications withincomputer 186 also include tire inflation specifications for theparticular tire and wheel assembly to be inflated, with suchspecifications including the target inflation pressure, as well asspecifications for positioning tire inflation head 40 such that thelocation of the circumferential sealing edge, such as sealing edge 108or sealing edge 128, is accurately located against the tire sidewall andmoved during the inflation process, as described below.

In the illustrated embodiment of FIG. 16, proportional position control184 is a proportional directional control valve. Alternatively,proportional position control 184 may be a servo hydraulic controlvalve.

In operation, with inflation head 40S in the retracted position 48, thepresence of a tire and wheel assembly, such as assembly 45 or 47,located at the assembly input location 34 is detected, such as by aphoto eye, vision system, or the like, or manually by activation of anoperator actuated switch, thus transmitting input signal 185 to computer186. With valves 176, 178 opened, hydraulic fluid is allowed to flow outof assist cylinders 44S, 46S through assist cylinder valves 180, 182whereby inflation head 40S is lowered into position against the tire andwheel assembly. Position information regarding the location of inflationhead 40S is transmitted by position transducer 84 to computer 186. Uponreaching a predetermined target position based on the particular tireand wheel assembly to be inflated, valves 176, 178 may be locked.Computer 186 may subsequently activate the flow of hydraulic fluidthrough proportional position control 184 to supply additional fluid toinflation cylinder 42S on one side or the other of piston 90S, with acorresponding amount of fluid removed from the opposite side of piston90S to accurately position inflation head 40S based on the tire andwheel assembly to be inflated. Subsequently, compressed air or the likewill be supplied through fluid passage 52 into inflation cavity 54 toinflate the tire. During inflation, control system 88 may continue tomonitor and control the position of inflation head 40S. For example, ifinflation head 40S is moved upwards due to the inflation pressure,additional hydraulic fluid may be supplied through proportional positioncontrol 184 into inflation cylinder 42S to readjust the position ofinflation head 40S. Proportional position control 184 may also be usedto gradually raise inflation head 40S during the inflation process tocoordinate the supplied air pressure through passage 52 to obtain thedesired tire inflation pressure. Upon obtaining the desired tireinflation pressure, or upon remaining in position for a predeterminedamount of time, valves 176, 178 may be opened to allow hydraulic fluidto flow out of inflation cylinder 42S and hydraulic fluid may be pumpedthrough assist cylinder valves 180, 182 into inflation cylinders 44S,46S to extend assist shafts 68, 70 and thereby raise inflation head 40S.

An additional feedback parameter for control system 88 may be themeasurement of inflation pressure, measured either during inflation suchas via pressure transmitting device 99 and/or measured as actual tireinflation pressure post the tire and wheel assembly being inflated byinflation apparatus 30. Input signal 183 supplied by pressuretransmitting device 99 to computer 186 may be used by computer 186 tocontrol the supply pressure and/or deactivation of pressurized fluidbeing supplied into inflation cavity 54. Moreover, the deactivation ofthe supply of pressurized fluid may be controlled and timed by computer186 to correspond with upward travel of inflation head 40S to minimizethe escape of pressurized fluid from the tire and wheel assembly. One ormore pressure transmitting devices may be alternatively located withininflation cavity 54, along fluid passage 52, or upstream thereof.

For example, upon detecting a particular tire and wheel assembly viainput signal 185, computer 186 controls the positioning of inflationhead 40S via input signal 181 to initially lower circumferential sealingedge, such as sealing edge 108 or sealing edge 128, to depress theupward facing tire sidewall to create a passage for pressurized gas intothe tire. Computer 186 then causes the air supply system to supply airthrough passage 52 and into cavity 54. In conventional manner, asignificantly higher supply pressure than the end target tire inflationpressure is initially provided to seat the tire bead of the lower tiresidewall on the wheel. Computer 186 may monitor the air pressure viainput signal 183 from pressure transmitting device 99 to confirm thathigh pressure has been obtained to confirm proper seating of the tirebead. Subsequently, computer 186 initiates inflation head 40S to beraised up via proportional position control 184 and the system airpressure supplied is reduced to the desired target tire inflationpressure via input signal 183 from pressure transmitting device 99, withinflation head 40S being raised until the tire bead of the upward facingsidewall is seated on the wheel. Upon detecting the proper inflationpressure and tire bead seat position of inflation head 40S via inputsignal 181, the supply of pressurized gas through passage 52 isterminated and head 40S may be rapidly raised via valves 176, 178.

Alternatively and/or additionally, tire inflation pressure may bemeasured after inflation head 40S is removed from a tire and wheelassembly, such as tire and wheel assembly 45 or 47. For example, tireand wheel assemblies may be provided with a tire pressure monitoring(TPM) valve stem (not shown) that is adapted to supply tire pressuredata to the vehicle to which it is mounted. Such a TPM valve stem may beused to supply tire inflation pressure of an inflated tire and wheelassembly to computer 186. In response, computer 186 may be used torefine the inflation of tire and wheel assemblies. For example,inflation pressure of pressurized fluid supplied to an assembly atinflation apparatus 30 may be increased or decreased in response topressure data supplied from a TPM valve stem. Additionally and/oralternatively, the positioning of inflation head 40S and/or the durationinflation head 40S is maintained in the tire engaging position 50 may beadjusted in response to such data. For example, inflation head 40S maybe positioned lower and/or remain in contact with the tire and wheelassembly longer in order to increase tire pressure in the assembled tireand wheel assembly.

Referring now to FIG. 17, an alternative embodiment of a control system188 for use with a tire inflation apparatus is disclosed, wherein theassist cylinders 190, 192 of the tire inflation apparatus areconstructed as pneumatic cylinders. Those portions of the inflationapparatus illustrated schematically in FIG. 17 corresponding withillustrated parts of FIGS. 1-15 are identified using like numbers asused in FIGS. 1-15, with 100 and the reference suffix “S” added to thelike illustrated parts in FIG. 17. Those schematically illustratedcomponents include an inflation head 140S, inflation cylinder 142S,inflation shaft 164S, piston 190S, and moveable cross member 171S.

Control system 188 includes directional valves 194, 196 tied topressurized gas source 198, which in the illustrated embodiment iscompressed air such as may be supplied by a shop air system. Controlsystem 188 also includes a bypass and lock up valve 200, a proportionalposition control 202, which in the illustrated embodiment is aproportional directional control valve, and a controller or processor,such as computer 204, or the like. Computer 204 interfaces and controlsvalves 200 and 202, as well as may receive input signals 181 fromposition transducer 84, input signals 183 from pressure transmittingdevice 99, and input signals 185 indicative of the presence and/orconfiguration of a tire and wheel assembly to be inflated. Controlsystem 188 operates in substantially similar manner as control system 88regarding operating the inflation process based on input signals 181,183, and 185, as such the specifics regarding inflation head positioningand pressure monitoring will not be discussed in detail relative tocontrol system 188.

Valve 200 is also a proportional flow control valve, which in theillustrated embodiment is a DIN cartridge valve, such as may be suppliedby the Parker Hannifin Corp., having an integrated position transducerfor monitoring the position of the internal valve spool that controlsthe flow rate of valve 200, with valve 200 being sized based on the flowrequirements necessary for the size tire and wheel assemblies to beinflated by apparatus 30. The proportional flow of valve 200 enablesrapid movement of inflation head 140S when valve 200 is fully opened,but provides finer positional control of inflation head 140S when flowis restricted from valve 200. When valve 200 is opened, hydraulic fluidis able to flow from one end of inflation cylinder 142S to the other oneither side of piston 190S to allow inflation shaft 164S to be rapidlyextended and retracted to position the attached inflation head 140S ineither a retracted position or the tire engaging position. As the targetup or down position of inflation head 140S is reached as monitored viaposition transducer 84 and input signal 181, the flow rate of valve 200is lowered by computer 204 to slow the travel rate of inflation head140S to thereby accurately control the stopping position of inflationhead 140S. Upon valve 200 being closed with inflation head 140S in thetire engaging position, inflation cylinder 142S is able to resist theupward force exerted on inflation shaft 164S by the inflation of a tireand wheel assembly.

Valve 200 may also be controlled via computer 204 to enable inflationhead 140S to be raised during the inflation operation after the initialoverpressure to seat the lower tire bead. That is, to enable inflationhead 140S to be raised while the system pressure is reduced to thetarget tire inflation pressure until the tire bead of the upward facingsidewall has been seated. Accordingly, control system 188 may bealternatively operated without proportional position control 202.Control system 188 further includes a safety feature via valve 200. Ifpower to control system 188 is lost, downward movement of inflation head140S via the weight of inflation head 140S will be resisted via thedischarge of hydraulic fluid from cylinder 142S into valve 200 toprovide a dead head flow condition.

Proportional position control 202 also operates in generally like mannerto proportional position control 184 of control system 88 to optionallyprovide finer position control of inflation head 140S. Positiontransducer 84 of inflation apparatus 30, monitors position of theinflation head 1408, such as by way of movement of moveable cross member171S. The position information from the position transducer istransmitted to computer 204, which in turn is able to activateproportional position control 202 to supply hydraulic fluid to inflationcylinder 142S and provide finer positioning of the inflation head 140Sas may be necessary. The use of accumulators 206, 208 enables the flowaverage to be leveled and permits a smaller hydraulic power supply to beused for the fine positioning of inflation head. Hydraulic fluid issupplied to the control system 188 by hydraulic power supply 210.

Pneumatic assist cylinders 190, 192 operate to move inflation head 140Sby acting on cross member 171S. For example, when inflation head 140S ispositioned in a tire engaging position and valve 200 is substantiallylocked against significant movement, pressurized air from pressuresource 198 is supplied through directional valves 194, 196 into assistcylinders 190, 192 such that assist cylinders 190, 192 are pre-chargedto exert an upward force on cross member 171S. When valve 200 is openedupon the completion of the inflation of a tire and wheel assembly, suchas assembly 45 or 47, assist cylinders 190, 192 subsequently driveinflation head 142S upward. Valve 200 is then again locked wheninflation head 142S reaches the desired position in the retractedposition. While valve 200 is locked with inflation head 142S in theretracted position, assist cylinders may again be recharged by pressuresource 198 to exert an opposite force on cross member 171S and, whenvalve 200 is reopened, assist cylinders can then drive inflation head140S into the tire engaging position. Directional valves 194, 196 ofassist cylinders 190, 192 may also be controlled by computer 204.

Control systems 88 and 188 thus provide closed loop control of theposition of the inflation head 40 of inflation apparatus 30 via activehydraulic control, as well as control based on inflation pressure andtire and wheel assembly parameters. Control systems 88 and/or 188 mayalternatively be used to monitor and control the operation ofalternative tire inflation apparatuses, and an inflation head 40 mountedto inflation shaft 42 of head positioning cylinder 42 may also beoperated by a conventional hydraulic circuit or system, and may includeconventionally operated assist cylinders as well, and still function asintended.

In the illustrated embodiment fixed frame member 62 is-secured to base32. It should be appreciated that alternative arrangements of fixedframe member, either with or without a base, may be employed and stillenable a tire inflation apparatus to function as intended within thescope of the present invention. For example, a fixed frame member maynot be unitarily attached to the structure whereat the assembled wheelrim and tire are held for inflation of the tire by the inflationapparatus. Such an arrangement may be achieved by forming the fixedframe member with overhead frame work independent of, for example, aconveyor system or line along which assembled wheel rims and tires areconveyed.

The tire inflation apparatus may be used as a standalone machine oroperation, or may alternatively be incorporated into an assembly line orassembly cell. For example, although not shown, tire inflation apparatus30 may be positioned adjacent a conveyor with mechanisms provided fortransferring tire and wheel assemblies from the conveyor for inflationand back to the conveyor upon being inflated. Still further, aconveyance system may be constructed to directly transport tire andwheel assemblies beneath the inflation head. A robotic insertion andremoval device may also be employed for loading and unloading tire andwheel assemblies from tire inflation apparatus 30.

An embodiment of the tire inflation apparatus in accordance with thepresent invention positions an inflation cylinder and assist cylindersabove the inflation head and pressurized gas is delivered to theinflation head through a fluid passageway formed in the shaft of theinflation cylinder. An inner and an outer bell assembly comprise theinflation head, with the outer bell assembly being selectively andreadily attachable and detachable from the inner bell assembly. Whendetached from the inner bell assembly, the outer bell assembly isretainable in a non-extended position such that the inner bell assemblymay be moved independently. The inflation apparatus inhibits debris andcontamination from disrupting the operation of the inflation head,provides a shorter height, and requires less power to operate. Moreover,the elimination of guide rods adjacent the wheel and tire assembly inputlocation provides greater access to the assembly input location, therebyenabling greater flexibility in the manufacturing process. The inflationapparatus further enables differently sized wheel and tire combinationsto be conveniently inflated without time consuming equipment changes.The inflation apparatus also simplifies the delivery of pressurized gasto a tire for inflation.

Changes and modifications in the specifically described embodiments canbe carried out without departing from the principles of the presentinvention which is intended to be limited only by the scope of theappended claims, as interpreted according to the principles of patentlaw including the doctrine of equivalents.

1. A tire inflation apparatus for inflating a tire mounted on a rim,said inflation apparatus comprising: a fixed frame member positionedabove a tire and rim assembly inflation location at which a tire mountedon a rim is received to inflate the tire; an inflation head, saidinflation head being movable between a retracted position and a tireengaging position, said inflation head defining a tire inflation cavityand adapted to form a seal with a tire when positioned against a tire insaid tire engaging position with pressurized gas deliverable into saidinflation cavity to inflate a tire when said inflation head is sealedagainst a tire in said tire engaging position; a head position cylinderincluding a fixed head position cylinder base and a moveable inflationshaft, said inflation head being mounted to said inflation shaft wherebymovement of said inflation shaft selectively positions said inflationhead between said retracted position and said tire engaging position;and a first assist cylinder mounted to said frame member above saidinflation location, said first assist cylinder including a fixed firstassist cylinder base and a moveable first assist shaft; said firstassist shaft being operatively connected to said inflation shaft by amoveable cross member with said head position cylinder and said firstassist cylinder cooperatively operating to selectively position saidinflation head, said inflation head being positioned in said retractedposition by vertical upward extension of said first assist shaft fromsaid first assist cylinder base and positioned in said tire engagingposition by vertical downward retraction of said first assist shaft intosaid first assist cylinder base.
 2. The tire inflation apparatus ofclaim 1, wherein said inflation shaft includes a fluid passage extendingat least partially through said inflation shaft, said fluid passageforming an outlet in said inflation cavity such that pressurized gas isdeliverable through said fluid passage to said inflation cavity.
 3. Thetire inflation apparatus of claim 2, further including a pressuretransmitting device, said pressure transmitting device operable tomonitor pressure at said inflation cavity.
 4. The tire inflationapparatus of claim 3, further including a tube positioned within saidfluid passage with an end of said tube positioned at said inflationcavity, and wherein said pressure transmitting device is mounted to saidtube for measuring pressure in said inflation cavity.
 5. The tireinflation apparatus of claim 1, wherein said cross member is positionedand moveable vertically above said frame member.
 6. The tire inflationapparatus of claim 5, wherein said first assist cylinder base member andsaid head position cylinder base are mounted to said frame member. 7.The tire inflation apparatus of claim 6, wherein said inflation shaftincludes a lower portion extending and retracting vertically downwardfrom said head position cylinder base and an upper portion extending andretracting vertically upward from said head position cylinder base, andwherein said upper portion of said inflation shaft is connected to saidmoveable cross member.
 8. The tire inflation apparatus of claim 1,wherein said first assist cylinder comprises a pneumatic cylinder. 9.The tire inflation apparatus of claim 1, further including a secondassist cylinder mounted to said frame member above said inflationlocation, said second assist cylinder including a fixed second assistcylinder base and a moveable second assist shaft; said second assistshaft being connected to said moveable cross member with vertical upwardextension of said second assist shaft from said second assist cylinderbase assisting positioning of said inflation head into said retractedposition and vertical downward retraction of said second assist shaftinto said second assist cylinder base assisting positioning of saidinflation head in said tire engaging position.
 10. The tire inflationapparatus of claim 1, further including at least one retainer mounted tosaid frame member and wherein said inflation head comprises an innerbell assembly and an outer bell assembly; said outer bell assembly beingselectively attachable to said inner bell assembly with said outer bellassembly forming a seal with a tire when engaged with said inner bellassembly and said outer bell assembly is positioned against a tire insaid tire engaging position; said outer bell assembly being selectivelydetachable from said inner bell assembly with said at least one retaineradapted to hold said outer bell assembly in said retracted position whensaid outer bell assembly is detached from said inner bell assembly; saidinner bell assembly being selectively moved independently of said outerbell assembly when said outer bell assembly is detached from said innerbell assembly with said inner bell assembly forming a seal with a tirewhen disengaged from said outer bell assembly and said inner bellassembly is positioned against a tire in said tire engaging position.11. The tire inflation apparatus of claim 1, further including; aposition gauge, said position gauge operatively detecting the positionof said inflation head; a controller, said controller operativelyconnected with said position gauge such that said controller receivesposition information of said inflation head; and a position controlvalve, said position control valve operatively connected with saidcontroller and adapted to control movement of said inflation head; saidcontroller adapted to operate said position control valve to directmovement of said inflation head in response to position information ofsaid inflation head received from said position gauge.
 12. A tireinflation apparatus for inflating a tire mounted on a rim, saidinflation apparatus comprising: a frame member positioned above a tireand rim assembly inflation location at which a tire mounted on a rim isreceived to inflate the tire; at least one retainer mounted to saidframe member; an inflation head movable between a retracted position anda tire engaging position, said inflation head defining a tire inflationcavity and adapted to form a seal with a tire when positioned against atire in said tire engaging position; a head position cylinder includinga fixed head position cylinder base and a moveable inflation shaft, saidinflation head being mounted to said inflation shaft whereby movement ofsaid inflation shaft selectively positions said inflation head betweensaid retracted position and said tire engaging position, said inflationshaft including a fluid passage extending at least partially throughsaid inflation shaft, said fluid passage forming an outlet in saidinflation cavity such that pressurized gas is deliverable through saidfluid passage to said inflation cavity to inflate a tire when saidinflation head is sealed against a tire in said tire engaging position;and said inflation head comprising an outer bell assembly and an innerbell assembly, said outer bell assembly being selectively attachable tosaid inner bell assembly with said outer bell assembly forming a sealwith a tire when engaged with said inner bell assembly and said outerbell assembly is positioned against a tire in said tire engagingposition; said outer bell assembly being selectively detachable fromsaid inner bell assembly with said at least one retainer adapted to holdsaid outer bell assembly in said retracted position when said outer bellassembly is detached from said inner bell assembly; said inner bellassembly being selectively moved independently of said outer bellassembly when said outer bell assembly is detached from said inner bellassembly with said inner bell assembly forming a seal with a tire whendisengaged from said outer bell assembly and said inner bell assembly ispositioned against a tire in said tire engaging position.
 13. The tireinflation apparatus of claim 12, wherein said inner bell assemblyincludes a plurality of locking pins, and wherein said outer bellassembly includes a moveable outer bell locking plate, said outer belllocking plate including a plurality of locking apertures, said lockingapertures selectively receiving said locking pins with said outer belllocking plate being moveable to selectively engage said outer bellassembly with said inner bell assembly and enable said outer bellassembly to be disengaged from said inner bell assembly.
 14. The tireinflation apparatus of claim 13, wherein said outer bell assemblyincludes a locking plate actuator, said locking plate actuator adaptedto rotate said outer bell locking plate relative to said inner bellassembly for engaging and disengaging said locking pins with saidlocking apertures.
 15. The tire inflation apparatus of claim 12, whereinsaid outer bell assembly includes at least one tab and wherein said atleast one retainer comprises at least one clamp, said at least one clampadapted to engage said at least one tab to hold said outer bell assemblyin said retracted position when said outer bell assembly is detachedfrom said inner bell assembly.
 16. The tire inflation apparatus of claim15, wherein said at least one clamp is actuated by a retention cylinder.17. The tire inflation apparatus of claim 12, further including a firstassist cylinder mounted to said frame member above said inflationlocation, said first assist cylinder including a fixed first assistcylinder base and a moveable first assist shaft; said first assist shaftbeing operatively connected to said inflation shaft by a moveable crossmember with said head position cylinder and said first assist cylindercooperatively operating to selectively position said inflation head,said inflation head being positioned in said retracted position byvertical upward extension of said first assist shaft from said firstassist cylinder base and positioned in said tire engaging position byvertical downward retraction of said first assist shaft into said firstassist cylinder base.
 18. The tire inflation apparatus of claim 12,further including; a position gauge, said position gauge operativelydetecting the position of said inflation head; a controller, saidcontroller operatively connected with said position gauge such that saidcontroller receives position information of said inflation head; and aposition control valve, said position control valve operativelyconnected with said controller and adapted to control movement of saidinflation head; said controller adapted to operate said position controlvalve to direct movement of said inflation head in response to positioninformation of said inflation head received from said position gauge.19. A tire inflation apparatus for inflating a tire mounted on a rim,said inflation apparatus comprising: a frame member positioned above atire and rim assembly inflation location at which a tire mounted on arim is received to inflate the tire; an inflation head, said inflationhead being movable between a retracted position and a tire engagingposition, said inflation head defining a tire inflation cavity andadapted to form a seal with a tire when positioned against a tire insaid tire engaging position; a head position cylinder including a fixedhead position cylinder base and a moveable inflation shaft, saidinflation head being mounted to said inflation shaft whereby movement ofsaid inflation shaft selectively positions said inflation head betweensaid retracted position and said tire engaging position; a positiongauge, said position gauge operatively detecting the position of saidinflation head; a controller, said controller operatively connected withsaid position gauge such that said controller receives positioninformation of said inflation head; and a position control valve, saidposition control valve operatively connected with said controller andadapted to control movement of said inflation head; said controlleradapted to operate said position control valve to direct movement ofsaid inflation head in response to position information of saidinflation head received from said position gauge.
 20. The tire inflationapparatus of claim 19, further including a pressure transmitting deviceoperative to monitor pressure at said tire inflation cavity and transmitinput signals indicative of the pressure at said tire inflation cavityto said controller, and wherein said controller is adapted to operatesaid inflation apparatus in response to said input signals.
 21. The tireinflation apparatus of claim 19, wherein said head position cylindercomprises a hydraulic cylinder and said inflation shaft includes apiston inside said head position cylinder base, and wherein saidposition control valve comprises a hydraulic proportional flow controlvalve adapted to supply and remove hydraulic fluid from both sides ofsaid piston.
 22. The tire inflation apparatus of claim 19, furtherincluding tire and wheel assembly data input signals supplied to saidcontroller, said data input signals comprising information indicative ofa tire and wheel assembly to be inflated with said controller operableto control operation of said inflation apparatus in response thereto.23. The tire inflation apparatus of claim 19, wherein said inflationshaft includes a fluid passage extending at least partially through saidinflation shaft, said fluid passage forming an outlet in said inflationcavity such that pressurized gas is deliverable through said fluidpassage to said inflation cavity to inflate a tire when said inflationhead is sealed against a tire in said tire engaging position.
 24. Thetire inflation apparatus of claim 23, further including a first assistcylinder mounted to said frame member above said inflation location,said first assist cylinder including a fixed first assist cylinder baseand a moveable first assist shaft; said first assist shaft beingoperatively connected to said inflation shaft by a moveable cross memberwith said head position cylinder and said first assist cylindercooperatively operating to selectively position said inflation head,said inflation head being positioned in said retracted position byvertical upward extension of said first assist shaft from said firstassist cylinder base and positioned in said tire engaging position byvertical downward retraction of said first assist shaft into said firstassist cylinder base.
 25. The tire inflation apparatus of claim 23,further including a tube positioned within said fluid passage with anend of said tube positioned at said inflation cavity and including apressure transmitting device, said pressure transmitting device beingmounted to said tube and operable to monitor pressure at said inflationcavity and transmit input signals indicative of the pressure at saidtire inflation cavity to said controller, and wherein said controller isadapted to operate said inflation apparatus in response to said inputsignals.